Generally images are generated and stored in the form of an image file having two components: the first component being an image data comprising pixel values that are capable of creating a visual image and the second component being a non-image data related to image parameters, image information properties, conditions, patient identification information, instrument manufacture information, technology information, etc. The non-image data can be stored in an image header or in an image trailer.
In the case of medical images as well, the images acquired include image data and non-image data. The medical images are generally stored in Digital Imaging and Communications in Medicine (“DICOM”) format. The non-image data could be stored in a header; the header does not contain pixel information, but contains other information such as the exact technique factors used during the image acquisition. The integrity of this other information, as it relates to a particular image, can be important in evaluating imaging security or quality of care at a specific institution. For example, investigators reviewing the quality of care provided to a patient may use the image data along with the non-image data during the course of a malpractice lawsuit.
The images acquired using different imaging systems and stored in different formats could be manipulated easily. In fact the image data and non-image data could be manipulated in different ways after the image has been stored and/or during transfer of the image file electronically or physically. Such manipulation can adversely affect the integrity of the image data, and make it difficult or impossible to rely on its accuracy.
Today, image-watermarking techniques can be used on image data to hide confidential or authorship information for the image. However there are no mechanisms to protect or detect manipulation of the non-image data. Today, one can read an image file, edit a non-image data associated with the image, and then re-save the image file. However, there is currently no way to identify or prevent the manipulation of the non-image data, thereby putting the integrity of the data into question. There are many lawsuits (e.g., malpractice lawsuits) which involve issues concerning manipulation or authenticity of the images and various other properties of the images. Thus securing the header information, which carries the non-image data of an image file, is very essential.
Thus, there exists a need to provide a method and system to determine the integrity of the non-image data and/or image data in an image file.